1 Defiant, popular name is SB-1 Defiant -->
Sikorsky Aircraft and
Boeing are jointly producing a medium-lift-sized demonstrator they named
SB>1 Defiant (also widely known as "SB-1") for phase one of the program. Originally planned to fly in late 2017, its
first flight was delayed in April 2017 to early 2018. Sikorsky led the initial development phase one with an aircraft based on their previous
Sikorsky X2 design while Boeing plans to led phase two, which is the mission systems demonstrator phase. The Boeing-Sikorsky team was seen to have an advantage with their large industrial base that may result in wider support from Congress alongside their transport helicopters being widely used by the U.S. Army. Up to 2013, Sikorsky and partners spent $250 million on X2 and Raider with a separate team and aircraft from the
S-97 Raider.
Swift Engineering Inc. supports the program with a major portion of the airframe structure designed and manufactured at the company's facility in San Clemente, California by an integrated team of Swift and Boeing employees. The timeline for the first flight slipped several times. Originally scheduled for 2017, delays arose due to a requirement to implement
automated fiber placement blade manufacture at the request of the U.S. Army. Further delays resulted in the first flight slipping past summer 2018. Dynamic systems such as
turboshafts,
transmission, and
rotors were scheduled to be tested at
West Palm Beach, Florida, by the end of October 2018, before ground runs in November, then first flight to reach within six months. Ground runs began in January 2019; 15 hours of ground tests were needed before the first flight. The first flight took place on 21 March 2019 at Sikorsky West Palm Beach site in Florida. In the summer of 2019, flights were suspended to address a bearing issue with the main rotor. Flight testing resumed on 24 September 2019. The aircraft reached a speed of 211 knots during level flight in October 2020. By December 2020, the demonstrator had logged 26 flight hours in 31 flights over the 21 months since first flight. By October 2021, the demonstrator reached a top speed of 247 knots in level flight.
Defiant X variant In January 2021, Sikorsky-Boeing announced the Defiant X variant, specifically designed for the
Future Long-Range Assault Aircraft program. In February 2022, Sikorsky-Boeing picked Honeywell's new HTS7500 engine, a derivative of the
Honeywell T55 engine that powered the SB-1 demonstrator, as the powerplant. In March 2022, Sikorsky-Boeing has selected
Collins Aerospace to provide all three seating platforms and its Perigon as
flight control computer. ==Design==